The present invention relates to a cap device for an ink jet recording head, which prevents ink settlings from attaching to the ink discharge holes of the recording head. More specifically, the cap device is used for tightly closing the ink discharge holes of the recording head when no printing operation is performed by the ink jet recording device, and for pulling ink to the ink discharge holes from the ink tank when the recording head is first used.
The cap device for an ink jet recording head has a cap of elastic material with an ink reservoir, which is used for forming a space to tightly close the ink discharge holes when it is brought into contact with the ink discharge face of the recording head. The cap device includes means for bringing the cap into contact with the discharge face, and fluid transporting means which pours forth fluid from the space formed between the ink discharge face and the ink reservoir.
Many space saving means have been employed for the cap device. Use of the ink suction pump of small size for the fluid transporting means is one of the space saving means.
A cap head for an ink jet recording head, which is used in the conventional ink jet recording apparatus, is disclosed in Japanese Patent Laid-Open Publication No. Hei. 3-5160. The ink suction pump includes a cylinder, a piston, disposed within the cylinder, having with a piston shaft through-hole and a seal rib formed on the end face of the piston as axially viewed, and a piston shaft, which passes through the through-hole, having a piston holder and a piston receiver, which are respectively disposed on the face of the piston having the seal rib and the face thereof opposed to the former in a state that the piston holder and the piston receiver are oppositely disposed with a predetermined space interposing therebetween. When the piston shaft is moved in the direction in which the piston holder pushes the piston, ink is sucked into the cylinder chamber. When the piston shaft is moved reversely, the sucked ink is discharged through the through-hole.
In the conventional cap device as mentioned above, the cap is moved when the cap having the ink reservoir on the front side is brought into contact with the ink discharging face of the recording head. Further, the piston is moved for operating the suction pump for sucking ink. The direction of the cap movement is different from the piston movement. Therefore, two drive mechanisms to drive the cap and the piston in different directions are required. Requirement of such two drive mechanisms results in complexity of the cap device structure, and hence hinders the size reduction of the cap device.